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Miller" , linux-sparc Subject: Re: [patch RFC 00/15] mm/highmem: Provide a preemptible variant of kmap_atomic & friends Message-ID: <20200924135805.GN2628@hirez.programming.kicks-ass.net> References: <87sgbbaq0y.fsf@nanos.tec.linutronix.de> <20200923084032.GU1362448@hirez.programming.kicks-ass.net> <20200923115251.7cc63a7e@oasis.local.home> <874kno9pr9.fsf@nanos.tec.linutronix.de> <20200923171234.0001402d@oasis.local.home> <871riracgf.fsf@nanos.tec.linutronix.de> <20200924083241.314f2102@gandalf.local.home> <20200924124241.GK2628@hirez.programming.kicks-ass.net> <20200924095138.5318d242@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200924095138.5318d242@oasis.local.home> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Sep 24, 2020 at 09:51:38AM -0400, Steven Rostedt wrote: > > It turns out, that getting selected for pull-balance is exactly that > > condition, and clearly a migrate_disable() task cannot be pulled, but we > > can use that signal to try and pull away the running task that's in the > > way. > > Unless of course that running task is in a migrate disable section > itself ;-) See my ramblings here: https://lkml.kernel.org/r/20200924082717.GA1362448@hirez.programming.kicks-ass.net My plan was to have the migrate_enable() of the running task trigger the migration in that case.